Process of smelting ores.



No. 821,159. PATENTED MAYVZZ, 1905.

' PRO ESS F SEJELTNG GRES,

xPLoATIo rum) mm1 27, 1905.

2 sHEBTs'-smm 1.

No. 821,189. y PATENTBD MAY 22, 1906. J. A. PQTTER. PROCESS o? SMELTNG- oms.

APPL .LTON FILED JUNE 27. 1905.-

' 2 SHEETS-*SHEET 2.

l UNTED STATES rarer cerros.

JOHN A. POTTER, OF SA FRANCISCO, OALiFORNlA.

enemies or' smi-:irme oase.

Specification of Letters Patent.

Patented May 22, 1906 Application filed June 27, 1905. Serial No. 267,302.

. esses of Smelting Ores,fo which the following is a specification.

This inventionl relates to an improved process of smeltin'g ores, particularly ferriferou's ores, the object being to provide a process by which, first-,the smelting maybe concombustion.

veniently accom lished on a large scale with the use of H uid els, such as petroleum-oils or fuel-gas; secondly, withwhich a compact .and economical apparatus may be A used;

thirdly, in which the operation` may be substantially continuous, and, fourthly, in which the cost of smeltin shall be reduced `to a minimum, *princi al y from the economical pro ortioning an application of the amounts of el used,l respectively, for reducing the oxid's and for the application or1 the heat of fusion.

In the accompanyin drawings, Figure 1 is a vertical section of t e apparatus. Fig. 2 is a similar View at right angles to Fig. 1. Fig. 3 isha horizontal section on the line 3 3 of Fig. 1. Fig. 4 is a horizontal section on the line 4 4 of Fig. 1.

Referring to the drawings, lvrepresents a rectangular iron casing inczlosing two regenerative chambers 2, provided with shelves 3 of rire-brick. Said chambers communicate at the bottom with iiues 4, leading to a stack 5, suitable reversing-dempers and air-inlet valves 6, such as is common in the art, being provided for changing the direction of the ingoing air and out'liowing gases. Between said regenerative chambers 2 is located a circular smelting-chamber 7 of lire-brick, the bottom of which is preferably formed of magnesite, over which pass the products of For said combustion Huid fuel, such as petroleum-oil or fuel-gas, is admitted through pipes 8, discharging into the air or gas conduits 9, leading i'om the tops oi said regenerative chambers I2to said open-hearth combustion or smeltingchamber 7. At the sides of said casing 1- are secured channelposts 10, which are connected by channelearns 11, across the mediate portions of vwhich are securedtransverse channel-beams 12,.to which are secured angle-iron brackets 14, which in tui'g are secured to the metallic casing of a retort. To the lower end of said retort-casing 15 is secured a metal ring 16, which serves the purpose of supporting the brickwork 170i said retort, said brick- Work consisting or" an inner cylindrical Wall 18, an outer cylindrical wall 19, and ribs connecting said walls for strengthening purposes and extending to a point near the top of the retort. The spaces 21 between these walls 18 19 and the ribs 20 serve as iiues through which the necessary hot gases from lthe combustion-chamber 7 pass, thereby hi lily heating said retort. Between the eircu ar top 22 of the open hearth or smeltin chamber 7 and the ring-casting 16 is built a roof or dome 23 of refractory material, as fire-brick, the top of saiddome being separated rom said ring-casting only by means of a water-cooled metallic top made in sections, as boxes 24, which can be separately withdrawn when necessary for the purpose of inspection or repairs. This withdrawal is permlssible by the fact that the retort does not, rest upon said boxes 24, but is su ported by the ring-casting 16 and the meta casing 15 which is in turn supported upon the channei-beams 13. Thus the necessary portion of the hot gases proceedin from the combustion-chamber 7, especial y those from the extreme to thereof, are allowed to escape through ho es 25 through said water-cooled boxes and ring-casting, and the-nee to pass into theiiues 21 ofthe retort to the top thereof, from any portion otwhich they can pass by the flue 26 to the main stack, the damper 27 being used to regulate the desired amount o'f gases to pass through the retort-iiues 21.

Upon the top of the retort is supported a hopper and dependent ring 28, into which the material ,canbe discharged by an suitable means, as by cars moving upon rai s 29, suitably sup orted upon a frame 30. middle o this frame is also mounted immediatelyV over the hopper a vertical hydraulic cylinder 31, the piston 32 of which is connected i with` a plunger 33, which can pass through the mouth of the hopper andfht with suiiicientcloseness therein to` substantially revent gases escaping from the retort-chamer. When it is desired to charge the retort, the lunger 33 is raised and the material which has been fed inte the hopper falls into the dependent ring in ihe-retort-chainber on the top ofthe previous charge. From the top of the retort-chamber pipes 34, convey In the j roo f mts mediate distilied therefrom to the conduits ey are burned with lthe fuel sup- .iough the pipes 8'. a tap-hole for drawing oli the molten nd at suitable intervals, dischargueinto a separator 36, from which s i. d' metal are withdrawn at diii'erent levels and disposed of.

When manufacturing cast-iron, as pig-iron,

the process is as follows: The ores to be reduced, also suitable quantities of limestone and tarry carbonaceous material, are all brought to a pulverulent or granular condition and are thoroughly commingled. On iirst commencing the process, which when once started. can be continued indefinitely, a shell, preferably of sheet metal 'of the same outside diameter as the interior of the retort, is inserted in the lower end of said retort, from which it extends to the bottom of the furnace-hearth, thus connecting the lower end ci the retort and furnace-bottom. The above t ixture discharged into the retort 'to i'ill s iell, and then heat is applied to the outside of said shell by the combustion of liquid fueladmitted through the pi es 8, said shell being slowly subjected to t e increasing heat of the liquid fuel, causing its contained mixture to become bound together and hardened by the oozing and charring of the tar and the coking of the combined carbon, after which it is melted at its lower end, at which timeI the heat in the furnace has been raised to such a degree 'that the continuous smelting process has commenced independent of any such extraneous means as that of the shell. The heat to which the mixture discharged into the retort sul'ijectcd. increases gradually as the material descends, and the effect of this heat applied on the outside of the column of the mixture is to first char the tar and coke the combined carbon which lforms a constituent of the outer layer or surface of the column, thus forming a hard binding crust or shell of carbon, lime, and ores bound togcther,'which crust or shell gradually increasesin thickness as the material descends into the lower and hotter zones of the retort, where the charring and coking operation extends into the interior of the column.' The effect'of this earlier charring process is to drive off the light hydrocarbon gases from the column of conuningled pulverized ores, limestone, and

' mirbonacecus material, said gases passing to 'the top of the retort, whence they are conveyed th rough the pipes 34- to the conduits 9 and are added to the fluid fuel used `for smelting and heating purposes. During the and later process of charring, b 1 g, and coking the hydrocarbon gases distilled from the carbonaceous material act as reducing agents on the ores commingled with said material, this reduction increasing as the heat becomes greater, since hotter on the top `gravity,

gases are distilled from the charred tar and combined carbon-coke of' the column. Said gases oozing from the interior pass through the porous,hard, and charred column and escape to the top of the retort; but as the material in its descent approaches the bottom ortion of the retort the gases so distilled, ollowin r the path of least resistance, tend to escape ownward into the furnace and combustion-chamber proper and are there burned, the products of combustion passing up through the flues of the retort, high ing the same, and finally out to the stack. Such hot reducing-gases constantly passing from the interionto the exterior of the column maintain a protection of the semimetallic particles that have formed on the exterior of the column from oxygen and oxidation during their exposure while traveling from the bottom of the retort through the furnace-chamber to the hottest part of the furnace, which is greatest just above the surface of the bath, at which point the heat completes the reduction of the ores, compelling the remainin oxygen thereof to unite with the solid car on contained in the column, while at the same time the lime has combined yheatwith the silicious and other earths of the column, formin a slag which gathers and floats o the metallic bath contained in the furnace-hearth. While this action is going on continuously, the metallic particles formed in the earlier stages of the process are constantly being attracted and fused together and formed -'nto a contracted fibrous metallic column intermingled with entrapped combined carbon, as coke, from the carbonaceous material which gradually descends withthe metallic column mto and under` the liquid bath of dissolving carbonaceous molten iron that is always maintained in the furnacehearth, where they are constantly being dissolved and v.amalgamated in said bath. The accumulating molten iron and slag are tapped off at suitable intervals into a metal and slag separator located on furnace-hearth, from where the metals and slags are drawn from diiferent levels for final distribution. lf the column should not gradually descend in the retrrt by its own it may be assisted from time to time by means of the plunger 33.

The c arbonaceous material to be used as a binding, reducing, and recarbonizing agent to be mixed with the ores and lime includes various materials--such` as residuum, asphaltum, coke, coal, charcoal, graphite, &c,- or it may be advantageous to mix any of the dry carbone with rcsduum, asphaltum, or oils, or the like.- The object of. using a tarry carbonaceous material is for two purposes, iirst', the contained tarry substances, which expand and ooze throughout the column of materials and as it is heated become charred, and thus7 together with the coke rethe outside of the IOO IOS

r passing-1.. the. .mixture sulting 'from the colring of the fixed carbon,` form a strong carbonaceous binder that binds v,the mass together, thus forming a column strong enough to withstand the downward and outward pressure of the superimpending portion thereof during the smelting process; secondly, the hot reducing carbonaceous gases generated from the charring and cokirig carbonaceous material at the different temperatures always act as an oxygen-consumer, oreredueer, metallic protector, and metal-recarbonirter throughout the whole process et heating, binding, charring, smelting, and dissolving.

bined carbon entrapped in the iron'column as it is descending and being immersed in the liquid bath is that a continual replenishment takes piace or" carbon in the liquid. bath, this being necessary to keep the liquid bath of the same constituency the same as that of pigiron--that is, a carbonaceous iron containing sufficient carbon. to furnish a solvent for the iron continually added thereto, increasing the iluidity of the iron, and maintaining its solvent effect. No mention has heretofore been made oi any ferriiierous ore except the ordinary iron ore; but the same process is applicable to a mixture oi ores necessary to produce any grade oi metal desired. Thus any kind of izerreous combination can be made by this process by adding the necessary ingredients, ores, metals, or metaloids--ior instance, a `lerricAmangent-isc or spiegeleisen or chromic metals, &c.

The constant veneration oi the reducin carbon gases forms a Very important part of the process, and a tarry carbonaceous material turnishcs these gases at all temperatures oi the process, as well as furnishes a strong binding material and solid carbon for final rcduction and the recarbonicing of the liquid bath. Carbon do most ot the oxygenciiinsuming in the early and intermediate stages of the process.

lt is to be understood. that my invention includes thel application of this process as applied to othcrmetals than iron so 'far as it may be found applicable thereto.

i. The process of smelting ores which consists in mixing` the orewith a material which when heated forms Vith said ore a binder,

ydownward through an open-bottomed 1e|ort,msiibjecting the mixture to al gradually-increasing heat as it through `the retort, whereby the body 'sQmate/rial so subieoted is hardened to prevent collapse, and applying a melting heat to The result oi the commipgling ci the com-- the material emerging from said retort, sub-- stantially as described,

The process of smelting iron ore, which. consists in mixing the ore with suitable quantities of limestone and hydrocarbonaceous material, passing the mixture so formedY 3. The process of smelting iron ore, which consists.. in reducing the ore, together with suitable quantities of limestone and hydrocarbonaceous material, to a .finely-divided condition and commingling the same, passing the mixture so formed into and through a retort, applying heat to the mixture increasing gradually as it passes through the retort'to gasi'fy, char and coke the hydrocarbonacecus material therein, applying products of combustion oi fluid fuel to the,exterior of the mixture to smelt the ore, drawing off the molten iron and slag at suitable intervals at one end of the apparatus and adding fresh material at suitable intervals at the other end of the apparatus, in a continuous process, substantially as described.

fi. The process ol' smelti'ng iron ore, which consists in ,finely dividing the ore and suitable quantities yof limestone and hydrocarbonaceous material and ,commingling the same, applying heat to the mixture to distil hydrocarbon gases therefrom and form a hard self-supporting column, and projecting such hard column into the path. of products of combustion to reduce and melt the metallic substances therein, substantially as described.

5. The process ci smelting iron ore, which consists in reducing said ore, together with suitable quantities of limestone and tarry carb onaeeous material, to a finely-divided condition and then commingling the same, continually feeding the mixture in proximity to increasing heats to form a hard column continually projecting said column into the path of products of combustion to reduce and melt the ore and metallic substances therein, and drawing oii at suitable intervals the molten iron and slag, substantially as described.

In witness whereof I have hereunto set my hand in the presence of two subscribing witnesses.

JOHN POTTER NWitnesses:

FnANcrs M. WRIGHT, Bassin Gonrrmrnr.

IIO 

